Fix indentation in double_click.

This was inadvertently over-indented by b33a3c9.

Author: juangj

py/selenium/webdriver/common/action_chains.py

@@ -160,8 +160,8 @@ def double_click(self, on_element=None):
         else:
             if on_element:
                 self.move_to_element(on_element)
-                self._actions.append(lambda: self._driver.execute(
-                                     Command.DOUBLE_CLICK, {}))
+            self._actions.append(lambda: self._driver.execute(
+                                 Command.DOUBLE_CLICK, {}))
         return self
 
     def drag_and_drop(self, source, target):